I imagine people are going through combinations of player's names and offensive terms until something pops up.

These have been, at least Hader and Newcomb, players specifically in the national spotlight at the moment. So some random fan (with Hader it was a Padres fan) does the search and finds the tweets and they spread pretty fast from there.

Players I would not lose sleep over losing/releasing would include Carlos Asuaje, Robbie Erlin, Phil Maton, Alex Dickerson, and Freddy Galvis (though it would be great to get some sort of compensatory pick for losing Galvis).

And of course trading Tyson Ross and/or Stammen would further alter the roster.

These have been, at least Hader and Newcomb, players specifically in the national spotlight at the moment. So some random fan (with Hader it was a Padres fan) does the search and finds the tweets and they spread pretty fast from there.